Method of making alpha fan



Sept. 6, 1932. E. MATHIS METHOD OF MAKING A FAN 2 Sheets-Sheet 1 Filed Dec. 51, 1951 Sept. 6, 3932. E. MATHIS 1,876,518

METHOD OF MAKING A FAN Filed D80. 31, 1931 2 Sheets-Sheet 2 I a .7 2 a .6. J C 5 Ia ewe J/faZ%z '5 7 parts in secton;

Patented Sept. -6, 1 932 UNITED STATES PATENT OFFICE EUGENE HATHIS, OF CHICAGO, ILLINOIS, ASSIGNOR TO NEW YORK BLOWER comm,

' DIE CHICAGO, ILLINOIS, A CORPORATION OF INDIANA.

vJlIE'IIIHOD OF MAKING A FAN Application filed December 31, 1931. serial Nq. 4,1Q2 A This invention relates to a method of making a fan. I

It has for one object to provide a fan in which the component parts are so shaped as to act as spacing and guiding members for manufacture, during the process of assembling. Another object is to provide a fan in A which the blades are themselves so shaped as to provide a positive engagement with the supporting parts. Another object is to provide such blades and to provide such positive engagementjduring the process of assembling and before the completion of manufacture. Another object is to provide a method of making a fan whereby the essential component parts of the fan are utilized during assembly as positioning andguiding means for assembly.

Other objects will appear from time to time in the specfication and claims.

My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein Figurel is a side elevation of a partially completed fan, with parts broken away and Figure 2 is a transverse cross section, taken at line 2-2 of Figure 1; I

' Figure? is a fragmentary endelevation of the outer ring of the completed fan;

Figure 4 is a transverse cross sectional detail taken on an enlarged scale, at line 4 1:

Figure 5 is a cross sectional detail taken on an enlarged scale at lines 55 of Figures 1 and 2; r

a Figure 6 isa side elevation of one of the blades in assembled position, showing its' relation to the rings-or other parts which it engages, a I

Figure 7 is a sectional detail on an en.- larged scale, taken at line 7 -7 of Figure '1;

, and l Figure'S is a side elevation of a blade, shown separately.

set screws A by means of which the hub is A, for example, by rivets B 2 parts are designated y like Characters throughout the specification and drawings.

" A is a hub which may have one or more held in fixed position upon a shaft A. The hub' is preferably provided with an outwardly and laterally flared web A. In the form here shown, the web terminates at its outer edge in a flat-sided annular portion A [which may be shaped along one side to pro vide a depression as at A Preferably, also, the annular portion A extends laterally beyond the outer end. of the hub proper, as indicated at X in Figure 2.

Positioned upon the annular portion A and resting partially in the depression A is a ring B. It may be secured to the annulus A It is preferably laterally bent so that its outer portion 13 lies generally in the same plane as the outer surface of the annulus A. A plurality of slots B is cut or otherwise formed in the flat outer portion B of the ring B, as indicated generally in Figure 1 andin detail in Fi ure-4. B is an annular corrugation.

' inner ring. It is also provided with slots C which correspond to the slots B of the inner ring B,-one slot C 'being normally placed opposite each slot B This relation is brought out particularly in the showing-of Figure5.

D isa blade which is preferably arcuate in cross section as shownparticularly in Figures 1, 3 and 4. nearly,suitable number of these blades may be. used, the number depending upon the size and type of the fan. The blade; is preferably-generally square across one end as shown particularly in Figures 6 to 8, inclusive, and the planefof its opposite end ispreferably turned at an angles of approximately 45 with respect to the plane of the square end. Each blade D is provided at its inner or square end witha pair of laterally extending lugs D D wh1ch extend outward at approximately a right angle with respect to the longitudinal axis of the blade. These lugs, in the assembled fan, contact the inner surface of the flattened portion B of the inner ring. The squared end of each blade is preferably provided with an additional lug D which may be situated between the two In s D and is arranged to be bent parallel to t em but offset from them a distance a proximately equal to the thickness of the attened portion B of the inner ring. Thus, in the assembled fan, the ring portion B is ripped between pairs of lugs D and a lug At its opposite end each blade is provided with two laterally extending lu D D which lie generally in the plane of the end. This end of each blade is also provided with an additional lug D one of which may be positioned intermediate each pair of lu s D. In the assembled fan, the lugs D are ent laterally to lie in a plane parallel to that of the lugs D but preferably ofl'set from them a distance approximately equal to the thickness of the ring C. This is illustrated generally in Figure 2 and in greater detail in Figures 6 and 7. In the assembled fan the lugs D and D are bent as shown generally in Figures 1 to 5, inclusive and in detail in Figure 6, and thus engage-each of the rings.

After the lugs have been bent into this position, they are permanently secured to the rings by welding, brazing or by soldering or otherwlse. In the form shown, the lugs are soldered as at E.

It will be realized that whereas I have herewith shown and described a practical operative device, nevertheless many changes might be made in the size, shape, number and disposition of parts, without departing from the spirit of m invention and I wish, therefore, that my sliowing be taken as in a sense diagrammatic.

The use and operation of my invention are as follows:

The fan of this invention may be used in a variety of associations where fans are desirable. Ordinarily two fans will be mounted together on a single shaft. Where that is done, they are made as rights and lefts and thus another fan similar to that shown in the drawings will be mounted to the right of the fan shown in Figure 2 on the shaft A and would be reversed with respect to it so that as the two rotate together, they discharge air in the same direction and work together in balanced relation.

Such fans are ordinarily mounted in a. housing or casing. The air is drawn in through one side of the fan and discharged peripherally by centrifugal force. The particular form of easing or association in which the fan is used forms no particular part of the present invention. Such fans, however, are frequently used as ventilating fans although their 7 tened in place before the blades are assembled and sometimes it is fastened afterwards. To assemble the blades, the inner ring B is held in position in any suitable manner. A suflicient number of blades D is then mounted upon it, each lu D projecting through a perforation B he outer or upper ring 0 is then positioned upon the blades so that one lug D projects through each of the slots or perforations G The two rings are positioned with respect to each other so that each slot C is directly opposite a slot 13 and thus the longitudinal axis of each blade D is at right angles to the plane of the flat portion B of the ring B. The rings and blades may be held during assembly. in any suitable fixture, arranged for positioning them and retaining them during assembly. The lugs D and D serve, of course, to position the two rings with respect to each other; since they are bent into the position shown in Figure 8 before assembly they serve as stops and when the rings are positioned they serve as positioning members for them. When each ring is, respectively, against the lugs at the inner and outer ends of the blades D, the two rings are properly spaced with respect to each other.

When all of the parts are in position, the lugs ,D and D are laterally bent asshown generally in all of the figures except 7 and 8. In that position each lug D holds a portion of the rim B of the ring B between itself and co-operating pairs of lugs D and each lug D holds a port on of the ring C between itself and co-operating pairs of lugs D Thus the rings are spaced by the blades and the thickness of the ring determines the point of bend of each lug D and D. When the lugs are so bent, they may then be secured in position by any suitable means. As shown in Figures 1, 3 and 5 they are soldered in position, although any other attaching means may be used. When the construction is complete each portion of each ring is not merely attached to a blade but is gripped securely between the lugs of each blade and since each end of each blade is thus in effect shaped along a flat surface,

shoulders are provided on the lugs for additionally stiffening the fan as a whole.

For some purposes it is desirable to bend the lugs D and fasten the blades at that end to the ring B before the upper or outer ring 6 is positioned and fastened. Ordinarily, however, the rings and blades will be assembled together before the bendin of thelugs and the final fastenin is accomp ished.

It is frequently ound, after the blades have been assembled in the holding parts C and B, that the heat which has been used in fastening the blades-to the holding arts, whether they be soldered, brazed, wel ed'or otherwise fastened, has resulted in'some distortion and misalignment, articularly of-the member B and it's fiattene portion B. For this reason the annular corrugation B is formed after the blades are assembled in'the holdin parts and its formation has the effect of straightening and re-alignin the member B, B and, of course, hasthe e ect of stiffening that member as a whole. For this and for other purposes, therefore, the annular corrugation B is frequentl formed in the member B, B? and normal y is formed cludes the after the fan as a whole has been assembled but before it has been mounted on thehub. It

may, of course, be omitted where it is not found necessary.

I claim:

1. The method of forming a fan which includes the following steps: forming a plurality of blade receiving members, forming a plurality of fan blades having at the endv of each of said blades a plurality of lugs in the plane of the blade, bending one of said lugs at each end of the blade out-of said plane to project outwardly from the face of. the blade, posltioning the blades in the blade receiving members withv said bent lugs iii-contact with one surface of each bladerecei'ving member, subsequently bending the remaining lugs at each end. of the blades to engage a'nfopposite surface of said members.

2. The method offorming afan whch includes the following steps: forming, a plurality of blade receiving members, forming a plurality of fan blades having at the end of each of said blades a plurality of lugs in the plane of the blade, bending a lurality of said lugs' at each end of the bla e out of said, plane toproject outwardly from the surface of the blade, positioning the blades in the blade receiving members with said bent lugs in contact with one surfaceof eachblade receiving member, subsequentl bending the remaining lugs at eachend o the blade to engage'an opposite surface of said members.

3. Themethod of forming a fan which infollowing steps: forming aplurality of blade rece ving members, forming a plurality of fan blades havingat the end of each of said blades a plurality oflugs in the plane of the blade, bending one of said lugs atjeach end of the blade out of said 'plane' to project outwardly from the surface of the blade, positionng the blades in the blade re{ ceiving members with said bent lugs in contact withone surface of each blade receivingmember,subsequently bending the remaining lugs at each end of the blade to engage an opposite surface of-said members, and additionall securin the parts in fixed position.

4; T emetho ofrformin [a fan which includes the following steps: ormin aplurality of blade receiving members, ormin'ga plurality of-fan blades having at the end ofeach of said blades a plurality of lugs in the lane of the blade, bending a plurality ofsaid ugs-at each end of the blade outof said plane to project outwardly from the surface ofthe blade, positioning the blades in the blade receiving members with said bent lugs in contact w th onesurface of each blade receiving member, subsequently bending the remaining lugs at each end ofthe blade to engage an opposite surface of said members, and additionally securing the parts infixed position.

5. The method of forming a fan which includes the following steps: forming a plurality of blade receiving members, each provided with perforations, formin a plurality of fan blades having at the end of each of said blades a plurality of lugs in the plane of the blade, bending a lurality of said lugs at each end of the bla e out of said plane to and with the remaininglugs at each end of the blade projecting through said erforations and subsequently bending sai remaining lugs to engage an opposlte surface of said 7 blade receiving member.

6. The method of forming a fan which in- I cludes the. following steps: forming a pluralit of blade receiving members, each provide withkperforations, forming a' lurality of: fan bla es' havingat the end 0' each of said blades a plurality of lugs in the lane of the blade, bendin a plurality of said lugs at each end of the b ade out of said plane to project outwardly from the face of the blade, positioning the blades in the blade receiving members with said bent lugs in contact with one surface of each blade receiving member and withtheremaininglu sat each end of the blade projecting throu h said erforations and subsequently ben ing sai remaining lugs to engage an opposite surface of said blade receiving mem er, and additionally securing the arts in fixed position. 7'. The met 0d of forming a fan which includes the following steps: forming-a plurality of blade receiving members, forming a pluralit of fan blades having at the on ofeach 0 said blades a plurality of lugs, in'

tact with one surface of each blade receiving- .member, subsequently bending the remaining lab lugsat each end of the blades to engage an no opposite surface of said blade receiving member, and subsequently forming in one of said blade receiving mem ers an annular corrugation.

8. The method of formin a fan whlch includes the following steps: ormin apluralit of blade receiving members, ormin a plzn-ality of fan blades having at the en of each of said blades a plurality of lugs in the plane of the blade, bending one of said lugs at each end of the blade out of said plane to roject outwardly from the surface of the blade, positioning the blades in the blade receiving members with said bent lugs in contact with one surface of each blade receiving member, subsequently bending the remaining lugs at each end of the blade to engage an opposite surface of said members, and additionally securing the parts in fixed position and subsequently forming in one of said blade receiving members an annular corru ation.

9. %he method of forming a fan which includes the following steps: forming a plurality of blade receiving members, forming a plurality of fan blades having at the end of each of said blades a plurality of In in the plane of the blade, bending one 0 said lugs at each end of the blade out of said plane to project outwardly from the surface of the blade, positioning the blade aevaeia positioning the blades in one of said blade receivin members with said bent lug in contact w1th one surface of said blade receiving I Signed at Chicago, county of Cookand State of Illinois, this 24th day of December,

EUGENE MATHIS,

receiving members with their surfaces angularly disposed with relation to each other, positioning the blades in the blade receiving members with said bent lugs in contact with one surface of each blade receiving member, subsequentl bending the remaining lugs at each end 0 the blade to engage an opposite surface of said blade receiving member.

10. The method of forming a fan which includes the following steps: forming a plurality of blade receiving members, forming one of said blade receiving members with two generally parallel flat surfaces, forming a plurality of fan blades having at the end of each of said blades a plurality of lugs in the plane of the blade, bending one of said lugs at each end of the blade out of said plane to project outwardly from the face of the blade, positioning the blades in the blade receiving members with said bent lugs in contact with one surface of each blade receiving member, subsequently bending the remaining lugs at each end of the blade to engage an opposite surface of said bladereceiving member, and thereafter forming an annular corrugation between the said two generally flatsurfaces of one of the blade receiving members. v

11. The method of forming a fan which inv eludes the following steps :forming aplurallty of blade receiving members, forming a.

plurality of fan blades having at one end a plurality of lugs in the plane of the blade, bending one of said lugs out of said plane to progect outwardly from the face of the blade, 

